1. Field of the Invention
The present invention relates to an electronic component module, and more particularly to an electronic component module in which a winding and an IC are embedded in a resin layer on the surface of a substrate.
2. Related Background Art
In recent years, small electronic devices such as mobile telephones have been configured using various electronic component modules that combine an inductor, a capacitor and other such elements with an IC. The high degree of component integration in electronic devices like mobile telephones seems without limits, and ever higher integration is being demanded in electronic component modules. For example, Japanese Patent Laid-open No. 2002-233140 discloses a micro power converter device, in which, subsequent to forming a winding that constitutes an inductor on a ferrite substrate and subjecting the winding to resin molding to inhibit the occurrence of saturation magnetization, a semiconductor substrate of a micro power circuit IC is laminated on top of the ferrite substrate that forms the winding.
However, the demand for higher integration and stable electrical characteristics in electronic devices knows no bounds, and there is demand for ever higher integration and more stable electrical characteristics in the electronic component module for use in power conversion described above.